This invention relates to water systems in contact with metallic surfaces, especially iron. Contact between water and the unprotected surface of iron, such as cast iron, or iron containing materials will result in the creation of a layer of ferric oxide, more commonly known as rust, on the metallic surface.
In certain industrial applications, cast iron components are subjected to conditions in which they are in contact with water. One such operation involves the production of cast iron diesel engines. During one phase of quality control testing of these engines, they are filled with water, drained and then removed to a storage location. The most corrosive environments can be found at the locations of stagnant pockets of residual water.
Under conditions where the metal is fully immersed in a dynamic environment, nitrite, borate, and silicate combinations have been utilized to effectively control corrosion for low carbon steel and cast iron. However, effective corrosion control cannot be maintained using these inhibitors either independently or in combination under stagnant, partially immersed conditions such as has been described above in the process of manufacturing diesel engines.